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1.
Chem Rec ; 24(1): e202300235, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37753795

RESUMO

Since the initial MXenes were discovered in 2011, several MXene compositions constructed using combinations of various transition metals have been developed. MXenes are ideal candidates for different applications in energy conversion and storage, because of their unique and interesting characteristics, which included good electrical conductivity, hydrophilicity, and simplicity of large-scale synthesis. Herein, we study the current developments in two-dimensional (2D) MXene nanosheets for energy storage and conversion technologies. First, we discuss the introduction to energy storage and conversion devices. Later, we emphasized on 2D MXenes and some specific properties of MXenes. Subsequently, research advances in MXene-based electrode materials for energy storage such as supercapacitors and rechargeable batteries is summarized. We provide the relevant energy storage processes, common challenges, and potential approaches to an acceptable solution for 2D MXene-based energy storage. In addition, recent advances for MXenes used in energy conversion devices like solar cells, fuel cells and catalysis is also summarized. Finally, the future prospective of growing MXene-based energy conversion and storage are highlighted.

2.
ACS Omega ; 8(24): 21898-21905, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37360446

RESUMO

Conventional methods for quantifying the added iron in wheat flour are time-consuming and costly. A rapid method (Time/Sample: 95 min) was developed by modifying the conventional standard method (Time/Sample: 560 min) and validated. Linearity and linear regression of the rapid method presented excellent correlation coefficient (R2) values (0.9976 to 0.9991), which were close to 1, while the limits of agreement (LOA) were in the range of -0.01 to 0.06 mg/kg. The limits of detection (LOD)/specificity and limits of quantitation (LOQ)/sensitivity values were found to be 0.03 and 0.09 mg/kg, respectively. The rapid method was subjected to validation, wherein the precision of intra-assay, inter-assay, and inter-person was determined to be within the range of 1.35-7.25%. These results indicate a high level of accuracy and precision of the method. The percent relative standard deviation (RSD) for recoveries at varying spiking levels, that is, 5, 10, and 15 mg/kg, was determined at 1.33 lying far below the upper limit of acceptability (RSD < 20). Overall, the developed rapid method can be sustainably alternate for conventional methods owing to its ability to produce accurate, precise, robust, and reproducible results.

3.
Environ Sci Pollut Res Int ; 29(5): 7214-7224, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34468945

RESUMO

Developing countries like Pakistan majorly depend on fossil fuels for achieving higher economic growth but have sloppy environmental rules and regulations in order to attract foreign direct investment (FDI). As a result, energy consumption is considered the primary cause of environmental degradation. Besides CO2 emission, environmental degradation is also associated with emission of sulfur dioxide (SO2). The purpose of this study was to investigate the relationship among SO2 emissions, energy consumption, economic growth, and FDI in Pakistan. By applying the 3SLS method, study has estimated the scale effect, composition effect, and technique effect. The scale effect and technique effect findings indicated that capital stock, FDI, and SO2 emissions all had a significant impact on GDP. When the capital accumulation effects of FDI were considered, the relationship between FDI and stock of capital was found to be positive. According to the technique effect results, FDI, population density, and energy consumption were all significantly related to SO2 emissions. The study came to a conclusion with significant policy implications.


Assuntos
Desenvolvimento Econômico , Dióxido de Enxofre , Dióxido de Carbono/análise , Investimentos em Saúde , Paquistão
4.
Can J Microbiol ; 66(2): 99-110, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31661630

RESUMO

This study examined the phylogenetic structure of serotype a Haemophilus influenzae (Hia) isolates recovered from patients in Canada. Hia isolates from 490 separate patients and an American Type Culture Collection (ATCC) strain were analyzed by multilocus sequence typing (MLST), with 18 different sequence types (STs) identified. Most (85.7%) Hia patient isolates were typed as ST-23 and another 12.7% belonged to 14 different STs with 6, 5, or 4 MLST gene loci related to ST-23 (ST-23 complex). Core genome single-nucleotide variation phylogeny (SNVPhyl) on whole genome sequence (WGS) data of 121 Hia patient isolates representing all identified STs and the ATCC strain revealed 2 phylogenetic populations, with all the ST-23 complex isolates within 1 population. The other phylogenetic population contained only the ATCC strain and 3 patient isolates. Concatenated hitABC sequences retrieved from WGS data and analyzed by MEGA (Molecular Evolutionary Genetic Analysis) alignment confirmed the phylogeny obtained by SNVPhyl. The sodC gene was found only in isolates in the minor phylogenetic population. The 2 phylogenetic populations of the Canadian Hia isolates are similar to the 2 clonal divisions described for serotype b H. influenzae. Combining MLST, core SNVPhyl, and hitABC gene sequence alignment showed that most (99.4%) Canadian Hia patient isolates belonged to 1 major phylogenetic population.


Assuntos
Infecções por Haemophilus/virologia , Haemophilus influenzae/genética , Sequenciamento Completo do Genoma , Canadá/epidemiologia , Pré-Escolar , Evolução Molecular , Feminino , Infecções por Haemophilus/epidemiologia , Haemophilus influenzae/imunologia , Humanos , Lactente , Masculino , Tipagem de Sequências Multilocus , Filogenia , Alinhamento de Sequência , Sorogrupo
5.
J Antimicrob Chemother ; 74(1): 22-28, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30295754

RESUMO

Objectives: Neisseria meningitidis is rarely penicillin resistant. We describe WGS analysis of a penicillin-resistant N. meningitidis collected from a case of invasive meningococcal disease. Methods: Serogrouping, serotyping and serosubtyping were performed with specific antibodies. ß-Lactamase was detected by nitrocefin. MICs were determined by Etest and agar dilution. Sequencing of N. meningitidis genomes was done on the Illumina MiSeq platform and genome data were analysed using the Bacterial Isolate Genome Sequence Database (BIGSdb) on the PubMLST Neisseria website (https://pubmlst.org/neisseria/). Transformation was used to confirm the genetic basis of the penicillin resistance. Results: An N. meningitidis blood isolate from a female patient in her mid-50s with a painful and septic left shoulder was found to have penicillin MIC values of 3-12 mg/L. The isolate was typed as Y: 14, 19: P1.- and ST3587, and was weakly ß-lactamase positive. WGS analysis identified a full-length copy of the ß-lactamase gene blaROB-1, which was contained on a 1719 bp insert with a G + C content of 41.7% (versus a G + C content of N. meningitidis of 51.7%), suggesting that the blaROB-1 gene came from a different bacterial species. A GenBank analysis of the blaROB-1 gene insert found 99.77% identity with a DNA segment found in plasmid pB1000' from Haemophilus influenzae. Transformation of a penicillin-susceptible strain with the blaROB-1 gene conferred ß-lactamase activity and penicillin resistance. Conclusions: N. meningitidis serogroup Y, ST3587 can carry and express the blaROB-1 gene, leading to penicillin resistance. It is highly likely that the N. meningitidis isolate acquired the blaROB-1 gene from H. influenzae.


Assuntos
Meningite Meningocócica/microbiologia , Neisseria meningitidis/genética , Resistência às Penicilinas , Sequenciamento Completo do Genoma , beta-Lactamases/genética , Composição de Bases , Feminino , Humanos , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Neisseria meningitidis/efeitos dos fármacos , Neisseria meningitidis/enzimologia , Neisseria meningitidis/isolamento & purificação , Sorotipagem , Transformação Bacteriana
6.
Int J Infect Dis ; 69: 55-62, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29414677

RESUMO

OBJECTIVES: This study was performed to analyze the Canadian invasive serogroup W Neisseria meningitidis (MenW) sequence type 11 (ST-11) clonal complex (CC) isolates by whole genome typing and to compare Canadian isolates with similar isolates from elsewhere. METHODS: Whole genome typing of 30 MenW ST-11 CC, 20 meningococcal group C (MenC) ST-11 CC, and 31 MenW ST-22 CC isolates was performed on the Bacterial Isolate Genome Sequence database platform. Canadian MenW ST-11 CC isolates were compared with the 2000 MenW Hajj outbreak strain, as well as with MenW ST-11 CC from other countries. RESULTS: Whole genome typing showed that the Canadian MenW ST-11 CC isolates were distinct from the traditional MenW ST-22 CC; they were not capsule-switched contemporary MenC strains that incorporated MenW capsules. While some recent MenW disease cases in Canada were caused by MenW ST-11 CC isolates showing relatedness to the 2000 MenW Hajj strain, many were non-Hajj isolates similar to current MenW ST-11 isolates found globally. Geographical and temporal variations in genotypes and surface protein antigen genes were found among the MenW ST-11 CC isolates. CONCLUSIONS: The current MenW ST-11 isolates did not arise by capsule switching from contemporary MenC ST-11 isolates. Both the Hajj-related and non-Hajj MenW ST-11 CC strains were associated with invasive meningococcal disease in Canada.


Assuntos
Técnicas de Tipagem Bacteriana , Infecções Meningocócicas/diagnóstico , Infecções Meningocócicas/epidemiologia , Neisseria meningitidis Sorogrupo C/genética , Neisseria meningitidis/genética , Adesinas Bacterianas/genética , Alelos , Antígenos de Bactérias/genética , Proteínas da Membrana Bacteriana Externa/genética , Proteínas de Bactérias/genética , Canadá/epidemiologia , Surtos de Doenças , Técnicas de Genotipagem , Humanos , Neisseria meningitidis/isolamento & purificação , Neisseria meningitidis Sorogrupo C/isolamento & purificação , Filogenia , Porinas/genética , Análise de Sequência de DNA , Sorogrupo
7.
Artigo em Inglês | MEDLINE | ID: mdl-28625140

RESUMO

BACKGROUND: With an increase in comprehension of the molecular biology of viruses, there has been a recent surge in the application of virus sequences and viral gene expression strategies towards the diagnosis and treatment of diseases. RESULTS: The scope of the patenting landscape has widened as a result and the current review discusses patents pertaining to live / attenuated viral vaccines. The vaccines addressed here have been developed by both conventional means as well as by the state-of-the-art genetic engineering techniques. CONCLUSION: This review also addresses the applications of these patents for clinical and biotechnological purposes.


Assuntos
Doenças dos Animais/terapia , Diabetes Mellitus Tipo 1/terapia , Patentes como Assunto , Vacinas Virais/uso terapêutico , Virologia/legislação & jurisprudência , Viroses/terapia , Animais , Sequência de Bases , Biotecnologia/métodos , Biotecnologia/tendências , Engenharia Genética/métodos , Engenharia Genética/tendências , Humanos , Fatores de Tempo , Vacinas Virais/genética , Virologia/métodos , Virologia/tendências
8.
Recent Pat Biotechnol ; 11(2): 141-151, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28260520

RESUMO

BACKGROUND: In consideration of recent developments in understanding the genomics and proteomics of viruses, the use of viral DNA / RNA sequences as well as their gene expression schemes, have found new in-roads towards the prognosis and therapy of diseases. Correspondingly, the sphere of the patenting scenario has expanded significantly. OBJECTIVES: The current review addresses patented inventions concerning the use of virus sequences as gene silencing machineries and inventions concerning the generation and application of viral sequences as expression vectors. Furthermore, this review also discusses the employment of these patents for clinical, agricultural and biotechnological applications. METHOD: Considering these objectives, the Delphion Research Intellectual Property Network database was searched using keywords such as "gene silencing", "engineered viruses" and "expression vectors" and descriptions of recent patents on the said topics were discussed. CONCLUSION: Despite several recent advances in the use of viruses as disease therapy vehicles and biotechnological vectors, these developments have yet to be proven effective in practice, in clinical and field trials.


Assuntos
Expressão Gênica , Inativação Gênica , Terapia Genética/legislação & jurisprudência , Vetores Genéticos , Vacinas de DNA , Vírus , Animais , Terapia Genética/métodos , Humanos , Patentes como Assunto
9.
Recent Pat Biotechnol ; 9(2): 79-85, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26961667

RESUMO

Recent innovative and advanced developments in the diagnosis and treatment of human diseases as well as enhanced in-depth understanding of virus molecular biology have opened novel avenues with respect to the patent landscape. Included are viruses utilized in the development of anticancer agents, agents that are employed against the spread of infectious viral diseases, RNA silencing agents and virus-derived expression vectors that can be used for over-expression of therapeutic proteins or as gene therapy vehicles. The current review describes several recent patents pertaining to virus sequences and their medical and biotechnological applications.


Assuntos
Terapia Genética/métodos , Neoplasias/terapia , Terapia Viral Oncolítica/tendências , Patentes como Assunto , Vetores Genéticos , Humanos , Neoplasias/genética , Neoplasias/virologia , Terapia Viral Oncolítica/métodos , Replicação Viral/genética
10.
Proc Natl Acad Sci U S A ; 111(40): 14542-7, 2014 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-25253891

RESUMO

The highly structured (64% GC) covalently closed circular (CCC) RNA (220 nt) of the virusoid associated with rice yellow mottle virus codes for a 16-kDa highly basic protein using novel modalities for coding, translation, and gene expression. This CCC RNA is the smallest among all known viroids and virusoids and the only one that codes proteins. Its sequence possesses an internal ribosome entry site and is directly translated through two (or three) completely overlapping ORFs (shifting to a new reading frame at the end of each round). The initiation and termination codons overlap UGAUGA (underline highlights the initiation codon AUG within the combined initiation-termination sequence). Termination codons can be ignored to obtain larger read-through proteins. This circular RNA with no noncoding sequences is a unique natural supercompact "nanogenome."


Assuntos
Regulação Viral da Expressão Gênica , Fases de Leitura Aberta/genética , Biossíntese de Proteínas/genética , RNA Viral/genética , RNA/genética , Sequência de Aminoácidos , Sequência de Bases , Northern Blotting , Western Blotting , Cromatografia Líquida , Códon de Iniciação/genética , Códon de Terminação/genética , Genoma Viral/genética , Dados de Sequência Molecular , Mutação , Peptídeos/genética , Peptídeos/metabolismo , RNA Circular , Espectrometria de Massas em Tandem , Proteínas Virais/genética , Proteínas Virais/metabolismo , Viroides/genética , Replicação Viral/genética
11.
Biochem Biophys Res Commun ; 452(1): 14-20, 2014 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-25117444

RESUMO

The construction of high-level protein expression vectors using the CaMV 35S promoter in concert with highly efficient translation initiation signals for Agrobacterium tumefaciens is a relatively less explored field compared to that of Escherichia coli. In the current study, we experimentally investigated the capacity of the CaMV 35S promoter to direct GFP gene expression in A. tumefaciens in the context of different viral and chloroplastic translation initiation signals. GFP expression and concomitant translational efficiency was monitored by confocal microscopy and Western blot analysis. Among all of the constructs, the highest level of translation was observed for the construct containing the phage T7 translation initiation region followed by the chloroplastic Rubisco Large Subunit (rbcL) 58-nucleotide 5' leader region including its SD-like sequence (GGGAGGG). Replacing the SD-like (GGGAGGG) with non SD-like (TTTATTT) or replacing the remaining 52 nucleotides of rbcL with nonspecific sequence completely abolished translation. In addition, this 58 nucleotide region of rbcL serves as a translational enhancer in plants when located within the 5' UTR of mRNA corresponding to GFP. Other constructs, including those containing sequences upstream of the coat proteins of Alfalfa Mosaic Virus, or the GAGG sequence of T4 phage or the chloroplastic atpI and/or PsbA 5' UTR sequence, supported low levels of GFP expression or none at all. From these studies, we propose that we have created high expression vectors in A. tumefaciens and/or plants which contain the CaMV 35S promoter, followed by the translationally strong T7 SD plus RBS translation initiation region or the rbcL 58-nucleotide 5' leader region upstream of the gene of interest.


Assuntos
Agrobacterium tumefaciens/genética , Caulimovirus/fisiologia , Cloroplastos/fisiologia , Biossíntese de Proteínas , Transdução de Sinais , Regiões 5' não Traduzidas , Sequência de Bases , Western Blotting , Primers do DNA , Eletroforese em Gel de Poliacrilamida , Elementos Facilitadores Genéticos , Proteínas de Fluorescência Verde/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
12.
Recent Pat DNA Gene Seq ; 5(3): 202-13, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21867477

RESUMO

Improved knowledge of the molecular biology of viruses, including recent gains in virus sequence data analysis, has greatly contributed to recent innovations in medical diagnostics, therapeutics, drug development and other related areas. Virus sequences have been used for the development of vaccines and antiviral agents to block the spread of viral infections, as well as to target and battle chronic diseases such as cancer. Virus sequences are now routinely employed in a wide array of RNA silencing technologies. Viruses can also be engineered into expression vectors which in turn can be used as protein production platforms as well as delivery vehicles for gene therapies. This review article outlines a number of patents that have been recently issued with respect to virus sequence data and describes some of their biotechnological applications.


Assuntos
Biotecnologia/legislação & jurisprudência , Vetores Genéticos , Patentes como Assunto , Interferência de RNA , Vírus/genética , Antivirais , Vacinas
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